5-i

CHAPTER 5. ENGINEERING ANALYSIS

TABLE OF CONTENTS

5.1 INTRODUCTION ........................................................................................................... 5-1

5.2 METHODOLOGY OVERVIEW.................................................................................... 5-1

5.2.1 Cost-Efficiency Analysis of Carbon Dioxide Refrigerant................................... 5-2

5.3 COST MODEL................................................................................................................ 5-2

5.3.1 Development of Core Case Costs........................................................................ 5-3

5.3.1.1 Selection of Units for Teardown Analysis................................................. 5-4

5.3.1.2 Manufacturer Production Cost Estimates and Assumptions...................... 5-5

5.3.1.3 Structure of the Cost Model ....................................................................... 5-5

5.3.1.4 Material Prices............................................................................................ 5-6

5.3.1.5 Results........................................................................................................ 5-7

5.3.2 Design Option Costs............................................................................................ 5-8

5.3.2.1 Light-Emitting Diode Price Forecasting .................................................... 5-8

5.3.3 Representative Unit Manufacturer Production Cost Values................................ 5-9

5.4 MANUFACTURER SELLING PRICE .......................................................................... 5-9

5.4.1 Manufacturer Markup .......................................................................................... 5-9

5.4.2 Shipping Costs................................................................................................... 5-10

5.5 ENERGY CONSUMPTION MODEL .......................................................................... 5-10

5.5.1 Screened-In Technologies.................................................................................. 5-11

5.5.2 Screened-In Technologies Not Considered in the Engineering Analysis.......... 5-11

5.5.2.1 Higher Efficiency Evaporator and Condenser Fan Blades....................... 5-12

5.5.2.2 Low-Pressure Differential Evaporators.................................................... 5-12

5.5.2.3 Improvements to Anti-Sweat Heaters ...................................................... 5-12

5.5.2.4 Variable-Speed Compressors................................................................... 5-12

5.5.2.5 Microchannel Heat Exchangers ............................................................... 5-13

5.5.3 Design Options................................................................................................... 5-13

5.5.3.1 Higher Efficiency Lighting ...................................................................... 5-13

5.5.3.2 Higher Efficiency Evaporator Fan Motors............................................... 5-15

5.5.3.3 Improved Evaporator Design ................................................................... 5-16

5.5.3.4 Insulation Increases or Improvements...................................................... 5-18

5.5.3.5 Improved Glass Pack................................................................................ 5-19

5.5.3.6 Higher Efficiency Condenser Fan Motors ............................................... 5-19

5.5.3.7 Improved Condenser Design.................................................................... 5-20

5.5.3.8 Higher Efficiency Compressors............................................................... 5-21

5.5.3.9 Lighting Controls ..................................................................................... 5-22

5.5.3.10 Refrigeration Low Power States .............................................................. 5-22

5.5.4 Baseline Specifications...................................................................................... 5-23

5.5.5 Non-Numerical Assumptions............................................................................. 5-26

5.5.6 Numerical Constants and Assumptions............................................................. 5-26

5.5.7 Model Components............................................................................................ 5-28

5.5.7.1 Component Energy Consumption ............................................................ 5-29

5.5.7.2 Compressor Energy Consumption ........................................................... 5-29
5-ii

5.5.7.3 Component Load Model........................................................................... 5-30

5.5.7.4 Radiation Load Model.............................................................................. 5-30

5.5.7.5 Conduction Load Model........................................................................... 5-30

5.5.7.6 Infiltration Load Model............................................................................ 5-31

5.6 COST-EFFICIENCY CURVES.................................................................................... 5-32

LIST OF TABLES

Table 5.3.1 Major manufacturing costs ............................................................................ 5-4

Table 5.3.2 Major manufacturing processes..................................................................... 5-6

Table 5.3.3 Calculated Core Case Costs........................................................................... 5-8

Table 5.5.1 Performance Details for “Class A Lighting” Design Option....................... 5-15

Table 5.5.2 Performance Details for “Class B Lighting” Design Option....................... 5-15

Table 5.5.3 Performance Details for “Evaporator Fan Motor” Design Option .............. 5-16

Table 5.5.4 Performance Details for “Improved Class A Evaporator Coil” Design 

Option .......................................................................................................... 5-16

Table 5.5.5 Performance Details for “Improved Class B Evaporator Coil” Design 

Option .......................................................................................................... 5-17

Table 5.5.6 Properties of Standard and Enhanced Class A Evaporator Coil.................. 5-17

Table 5.5.7 Properties of Standard and Enhanced Class B Evaporator Coil .................. 5-18

Table 5.5.8 Performance Details for “Improved Glass Pack” Design Option................ 5-19

Table 5.5.9 Performance Details for “Improved Glass Pack” Design Option................ 5-19

Table 5.5.10 Performance Details for “Improved Class A Condenser Coil” Design 

Option .......................................................................................................... 5-20

Table 5.5.11 Performance Details for “Improved Class B Condenser Coil” Design 

Option .......................................................................................................... 5-20

Table 5.5.12 Properties of Standard and Enhanced Class A Condenser Coil................... 5-21

Table 5.5.13 Properties of Standard and Enhanced Class B Condenser Coil................... 5-21

Table 5.5.14 Baseline Specifications................................................................................ 5-23

Table 5.5.15 Class A Equipment Class Baseline Specifications ...................................... 5-24

Table 5.5.16 Class B Equipment Class Baseline Specifications....................................... 5-25

Table 5.5.17 Combination Vending Machine Equipment Class Baseline 

Specifications............................................................................................... 5-25

Table 5.5.18 Energy Consumption Model Numerical Constants and Assumptions......... 5-27

Table 5.5.19 Engineering Constants................................................................................. 5-28

Table 5.6.1 Cost Efficiency Data for the R-134a Class A – Small Analysis Point ........ 5-34

Table 5.6.2 Cost Efficiency Data for the R-134a Class A – Medium Analysis Point .... 5-35

Table 5.6.3 Cost Efficiency Data for the R-134a Class A – Large Analysis Point ........ 5-36

Table 5.6.4 Cost Efficiency Data for the R-134a Class B – Small Analysis Point......... 5-38

Table 5.6.5 Cost Efficiency Data for the R-134a Class B – Medium Analysis Point .... 5-39

Table 5.6.6 Cost Efficiency Data for the R-134a Class B – Large Analysis Point......... 5-40

Table 5.6.7 Cost Efficiency Data for the R-134a Combo A - Medium Analysis 

Point............................................................................................................. 5-42

Table 5.6.8 Cost Efficiency Data for the R-134a Combo A – Large Analysis Point ..... 5-44
5-iii

Table 5.6.9 Cost Efficiency Data for the R-134a Combo B - Medium Analysis 

Point............................................................................................................. 5-46

Table 5.6.10 Cost Efficiency Data for the R-134a Combo B – Large Analysis Point ..... 5-48

Table 5.6.11 Cost Efficiency Data for the R-744 Class A – Small Analysis Point .......... 5-49

Table 5.6.12 Cost Efficiency Data for the R-744 Class A – Medium Analysis Point...... 5-50

Table 5.6.13 Cost Efficiency Data for the R-744 Class A – Large Analysis Point .......... 5-51

Table 5.6.14 Cost Efficiency Data for the R-744 Class B – Small Analysis Point .......... 5-53

Table 5.6.15 Cost Efficiency Data for the R-744 Class B – Medium Analysis Point ...... 5-54

Table 5.6.16 Cost Efficiency Data for the R-744 Class B – Large Analysis Point .......... 5-55

Table 5.6.17 Cost Efficiency Data for the R-744 Combo A – Medium Analysis 

Point............................................................................................................. 5-57

Table 5.6.18 Cost Efficiency Data for the R-744 Combo A – Large Analysis Point....... 5-59

Table 5.6.19 Cost Efficiency Data for the R-744 Combo B - Medium Analysis Point.... 5-61

Table 5.6.20 Cost Efficiency Data for the R-744 Class A – Small Analysis Point .......... 5-63

LIST OF FIGURES

Figure 5.3.1 Metal Price Trends .................................................................................................. 5-7

Figure 5.5.1 Components of the Energy Consumption Model......................................... 5-29

Figure 5.6.1 Cost-Efficiency Curve for the R-134a Class A – Small Analysis Point...... 5-34

Figure 5.6.2 Cost-Efficiency Curve for the R-134a Class A – Medium Analysis 

Point............................................................................................................. 5-35

Figure 5.6.3 Cost-Efficiency Curve for the R-134a Class A – Large Analysis Point...... 5-36

Figure 5.6.4 Cost-Efficiency Curve for the R-134a Class B – Small Analysis Point...... 5-37

Figure 5.6.5 Cost-Efficiency Curve for the R-134a Class B – Medium Analysis 

Point............................................................................................................. 5-39

Figure 5.6.6 Cost-Efficiency Curve for the R-134a Class B – Large Analysis Point...... 5-40

Figure 5.6.7 Cost-Efficiency Curve for the R-134a Combo A – Medium Analysis 

Point............................................................................................................. 5-41

Figure 5.6.8 Cost-Efficiency Curve for the R-134a Combo A – Large Analysis 

Point............................................................................................................. 5-43

Figure 5.6.9 Cost-Efficiency Curve for the R-134a Combo B - Medium Analysis 

Point............................................................................................................. 5-45

Figure 5.6.10 Cost-Efficiency Curve for the R-134a Combo B – Large Analysis 

Point............................................................................................................. 5-47

Figure 5.6.11 Cost-Efficiency Curve for the R-744 Class A – Small Analysis Point........ 5-49

Figure 5.6.12 Cost-Efficiency Curve for the R-744 Class A – Medium Analysis 

Point............................................................................................................. 5-50

Figure 5.6.13 Cost-Efficiency Curve for the R-744 Class A – Large Analysis Point........ 5-51

Figure 5.6.14 Cost-Efficiency Curve for the R-744 Class B – Small Analysis Point........ 5-52

Figure 5.6.15 Cost-Efficiency Curve for the R-744 Class B – Medium Analysis Point.... 5-54

Figure 5.6.16 Cost-Efficiency Curve for the R-744 Class B – Large Analysis Point........ 5-55

Figure 5.6.17 Cost-Efficiency Curve for the R-744 Combo A – Medium Analysis 

Point............................................................................................................. 5-56

Figure 5.6.18 Cost-Efficiency Curve for the R-744 Combo A – Large Analysis Point .... 5-58
5-iv

Figure 5.6.19 Cost-Efficiency Curve for the R-744 Combo B - Medium Analysis 

Point............................................................................................................. 5-60

Figure 5.6.20 Cost-Efficiency Curve for the R-744 Class A – Small Analysis Point........ 5-62
5-1

CHAPTER 5. ENGINEERING ANALYSIS

5.1 INTRODUCTION

The engineering analysis establishes the relationship between manufacturer selling price 

(MSP) and daily energy consumption (DEC), measured in kilowatt hours per day (kWh/day), for 

the refrigerated beverage vending machines (BVMs) covered in this rulemaking. This costefficiency relationship serves as the basis for cost/benefit calculations for individual customers, 

manufacturers, and the nation. 

The primary inputs to the engineering analysis are baseline information and data for each 

equipment class addressed in the market and technology assessment (chapter 3 in this technical 

support document (TSD)) and technology options from the screening analysis (chapter 4 in the 

TSD). Additional inputs include cost and energy consumption data that the U.S. Department of 

Energy (DOE) developed using a cost model and an energy-consumption model, respectively. 

The primary outputs of the engineering analysis are a set of cost-efficiency curves and a 

manufacturer markup multiplier used to convert manufacturer production cost (MPC) to MSP. 

In the subsequent markups analysis (chapter 6 in the TSD), DOE determines customer prices by 

applying distribution markups, sales tax, and contractor markups. After applying these markups, 

the data serve as inputs to the energy use characterization (chapter 7 in the TSD) and the lifecycle cost and payback period analyses (chapter 8 in the TSD). 

In this chapter, DOE discusses representative baseline units, the methodology used to 

develop MPC, markups applied to convert MPC to MSP, and the methodology used to estimate 

energy consumption. DOE also presents the resulting cost-efficiency curves.

5.2 METHODOLOGY OVERVIEW

This section describes the analytical methodology used in the engineering analysis. In 

this rulemaking, DOE is adopting a design-option approach, which calculates the incremental 

costs of adding specific design options to a baseline model. DOE used six different analysis 

points each for Class A and Class B equipment, and eight total analysis points for combination 

vending machines. Representative small-, medium-, and large-sized machines were analyzed for 

Class A and Class B machines. These sizes were based on a survey of equipment conducted 

during the 2009 rulemaking and corroborated with stakeholder input after the framework stage of 

the current rulemaking. Two representative sizes each were analyzed for combination vending 

machines with a fully-cooled refrigerated compartment (Combo A) and combination vending 

machines with a refrigerated compartment that is not fully-cooled (Combo B equipment). All 

combinations of class and representative size were analyzed both for equipment using HFC-134a 

refrigerant and for equipment using carbon dioxide (R-744) refrigerant, resulting in a total of 20 

analysis points. See chapter 3 of the TSD for a detailed description of the equipment classes and 

section 5.5.4 for additional detail on the different sizes of machines analyzed.

For each analysis point, DOE developed a core case cost using a manufacturing cost 

model. The core case cost is the MPC of the structure, walls, doors, shelving and fascia of the 

case, but does not include the cost of any energy-using components. DOE then developed 
5-2

pricing independently for each design option and added the design option pricing to the core case 

costs to arrive at total MPC values for each combination of equipment class, size, refrigerant, and 

design option configuration. DOE also calculated the impact of each design option on DEC 

using an energy consumption model. DOE then conducted a markups analysis to translate MPC 

to MSP. 

The primary results of the engineering analysis are a set of cost-efficiency curves, in the 

form of MSP versus DEC, for each of the 20 analysis points. 

5.2.1 Cost-Efficiency Analysis of Carbon Dioxide Refrigerant

As mentioned above, cost-efficiency curves were developed both for units that use R134a refrigerant and those that use carbon dioxide refrigerant for each of the ten equipment type 

and size combinations analyzed. The result is a total of twenty analysis points and corresponding

cost-efficiency curves. The modeling for each carbon dioxide refrigerant analysis point differed 

from that for the analogous R-134a analysis point in the MPC associated with each of three 

components: baseline and improved evaporator design, baseline and improved condenser design, 

and baseline and higher efficiency compressors, as well as the daily energy use associated with 

baseline and higher efficiency compressors. Additionally, different design options were modeled 

in the representative baseline units for those equipment classes that are currently subject to DOE 

standards for equipment using carbon dioxide refrigerant. Please see the respective design option 

subsections for details regarding the energy consumption and MPC calculations, and the 

introduction to Section 5.5 as well as Appendix 5A for further information regarding the 

modeling of baseline units. 

5.3 COST MODEL

One major output of the engineering analysis is the development of costs for the 

representative units analyzed at the baseline and at each higher design option level. These values 

were developed using a cost model that was divided into two parts for this rulemaking. The first 

of these was a stand-alone cost model, based on physical teardowns of refrigerated beverage 

vending machines, that was used for developing the core case costs. These core case costs 

consisted of the costs to manufacture the refrigerated case itself, consisting of structural 

members, shelving, wiring, vending systems, and so on, without the components that could 

directly affect energy consumption. The second part of the cost model was a component of the 

engineering analytical model and operated in unison with the energy consumption model. This 

model received inputs in the form of the core case costs and the prices for design options 

implemented at and above the baseline, such as baseline and improved glass doors, higher 

efficiency compressors, and higher efficiency lighting. These two sets of data (core case costs 

and design option costs) were used to build up total system costs for each analysis point at each 

design option level modeled.
5-3

5.3.1 Development of Core Case Costs

The development of the case costs was based on physical teardowns of Class A and Class 

B units available on the market at the time of the analysis. The first step in the assessment was 

the creation of a complete and structured bill of materials (BOM) from the disassembly of 

refrigerated beverage vending machines. DOE dismantled each unit and characterized each part 

according to weight, manufacturing processes, dimensions, material, and quantity. The result was 

a set of BOMs that included the costs for materials, components, and fasteners, and contained 

estimates for the cost of raw materials and purchased parts and other costs such as labor, 

depreciation, and overhead. DOE based assumptions about the sourcing of parts and in-house 

fabrication on industry experience and information from trade publications. The BOMs from the 

teardowns were fed into a factory model to produce estimates of MPCs for each of the units 

analyzed. Those estimates were then expanded to produce case costs for the analysis points not 

directly examined via teardown. The cost model was based on production activities and divided 

factory costs into the categories shown in Table 5.3.1.
5-4

Table 5.3.1 Major manufacturing costs

Major Category Sub-Category Description

Material Costs

Direct Raw materials (e.g., coils of sheet metal) and 

purchased parts (e.g., fasteners, wiring)

Indirect Supplies (e.g., welding rods, die oil, release media)

Labor

Assembly Parts/unit assembly on manufacturing line

Fabrication Conversion of raw material into parts ready for 

assembly

Indirect

Fraction of overall labor not associated directly with 

equipment fabrication or assembly (e.g., forklift 

drivers, quality control, purchasing of raw material 

and tools)

Supervisory Fraction of assembly, fabrication, and indirect labor 

that is paid a higher wage

Depreciation

Equipment, 

Conveyor, Building Straight-line depreciation over expected life

Tooling Cost is allocated on a per-use basis or obsolescence, 

whichever is shorter

Other Overhead

Utilities A fixed fraction of all material costs meant to cover 

electricity and other utility costs

Facility and 

Equipment 

Maintenance

Based on installed equipment and tooling investment

Property Tax and 

Insurance A fixed fraction based on total unit costs

The cost model analysis created cost estimates for each of the BVM analysis points. The 

cost model used certain assumptions to provide cost estimates; the following sections describe 

those assumptions. 

5.3.1.1 Selection of Units for Teardown Analysis 

The selection of units for physical teardown analysis was performed in a manner so as to 

allow for the greatest coverage of the range of equipment modeled in this analysis across a 

variety of manufacturers, sizes, and efficiency levels. The equipment selected came from both 

Class A and Class B in a variety of configurations. The equipment was chosen from the product 

lines of a variety of manufacturers and at sizes similar to what DOE had determined would be an 

appropriate representative unit size for the given equipment class. DOE did not conduct any 

physical teardowns of combination equipment, but rather extended its modeling of Class A and 
5-5

Class B equipment to develop models of combination equipment based on the transferrable

physical similarities between the analogous classes. 

5.3.1.2 Manufacturer Production Cost Estimates and Assumptions

MPC includes the sum of direct labor, direct materials, and overhead, including 

investment depreciation. The cost of specific models―or costs to individual 

manufacturers―will vary, depending on the equipment’s precise characteristics, the actual 

manufacturing processes, the equipment mix in the factory, and other elements. There may also 

exist differences in the levels of vertical integration that affect cost structure and thus the cost of 

equipment; companies with a large market share and/or revenue base tend to be more vertically 

integrated than their smaller competitors. Yet, DOE assumed that all manufacturers buy at least 

some of their parts and/or subsystems from outside vendors. 

DOE built a parametric model that allowed the scaling of input factors. The assumptions 

behind the model are based on published data by manufacturers, general industry practice, and 

previously published DOE reports. DOE compared the model results to published unit data and 

market prices. For example, DOE compared listed shipping weights with the calculated weights 

for cabinets of representative units as a method of checking its results.

The lack of specific information on manufacturing practices and facilities within the 

industry made calculating representative investment requirements difficult. Market shares, scales 

of operation, and levels of vertical integration may vary across manufacturers and equipment 

classes, and higher volume manufacturers may derive a cost advantage based on their purchasing 

volume for common raw materials and purchased parts alike. Lacking detailed data, DOE did not 

try to account for low- versus high-volume purchasing power in the development of the cost 

model, instead using industry-averaged aggregate data to represent all equipment offerings 

modeled.

5.3.1.3 Structure of the Cost Model

DOE used a detailed, component-focused manufacturing cost assessment methodology to 

estimate the BVM MPCs through use of the cost model, taking into account, for example, direct 

materials, direct labor, and factory overhead costs.

Following the development of detailed BOMs for each piece of equipment physically 

examined, DOE identified the major manufacturing processes and developed the spreadsheet 

model. Table 5.3.2 lists these examples of these processes.
5-6

Table 5.3.2 Major manufacturing processes

Fabrication Finishing Assembly/Joining

Fixturing Washing Adhesive bonding

Stamping/pressing Powder coating Spot welding

Brake forming De-burring Seam welding

Cutting and shearing Polishing Inspecting and testing

Insulating - -

DOE estimated fabrication process cycle times and entered them into the BOM. For this 

analysis, DOE estimated an average fully burdened hourly cost of labor based on the typical 

annual wages and benefits of industry employees. In the final step of the cost assessment, DOE 

estimated assembly times and associated direct labor costs.

Once the cost estimate for each unit was finalized, DOE prepared a detailed summary of 

relevant components, subassemblies, and processes. In order to yield costs for the refrigerated 

case structures and not the design option components, assemblies accounted for by the design 

options (e.g., glass doors, heat exchangers) were stripped away from the BOMs for each unit. 

The result was a set of costs corresponding to the MPCs for the core cases of each of the units 

analyzed.

The final step in the cost modeling process was to expand the results to apply to the 

remainder of the analysis points, including those corresponding to combination vending 

machines, for which teardowns were not performed. To achieve this, DOE added parametric 

scaling features to the model, which allowed the teardown units to be virtually scaled by size 

within the model. The end result was a full set of 10 core case costs, which served as the starting 

point for the development of whole-system costs at the baseline and improved design option 

levels in the engineering model.

5.3.1.4 Material Prices

The cost model uses multiple proprietary databases to determine raw material costs and 

purchased part prices. Prices for most inputs are based on the most up-to-date data that the DOE 

has been able to obtain, and past quotes are inflated as needed using appropriate Bureau of Labor 

Statistics (BLS) Producer Price Index (PPI) inflators as necessary. For example, the BLS carries 

a PPI for fractional electric motors that DOE uses to inflate past quotes on fractional motors to 

the present day. DOE recognizes that the BLS does not furnish a PPI for every purchased part 

that may be used by a manufacturer; in these instances, DOE substitutes appropriate PPI series 

whose trends should be similar or uses inflators from commercial data suppliers. For example, 

DOE uses the HARPEX indicator to determine shipment costs for container loads. (The 

HARPEX shipping index tracks weekly container shipping rate changes in the time charter 

market for eight classes of all-container ships.) When possible, purchased part prices and raw 

material costs are reviewed with manufacturers at the appropriate purchasing volumes for 

accuracy.
5-7

DOE research suggests that metal prices are very volatile and that the raw materials used 

by manufacturers can vary significantly in price as a function of when the data were collected. In 

order to reduce the potential impact that temporarily high or temporarily low metal prices can 

have on the analysis, DOE uses a 5-year moving average price for all metal raw material prices. 

A moving average helps address significant price swings in commodities such as copper, whose 

free market price ranged from $2.2 to $4.5 a pound within the last 5 years. The current 5-year 

average for copper is about $3.5/lb. Other commodities like aluminum had smaller absolute price 

changes, ranging from about $0.9 to $1.3 per pound. 

Figure 5.3.1 shows the prices associated with 304-grade stainless steel (SS304), free 

market copper (Cu), and aluminum (Al), normalized back to January 2003.

Figure 5.3.1 Metal Price Trends

5.3.1.5 Results

Core costs, defined as MPC minus the cost of design options, were calculated for 

multiple sizes of each equipment class. Table 5.3.3 displays these results. 
5-8

Table 5.3.3 Calculated Core Case Costs

Equipment Class Refrigerated Volume 

(ft3) Size Designation Calculated Core Cost$

Class A 17 Small 1,346

Class A 22 Medium 1,373

Class A 34 Large 1,425

Class B 17 Small 1,243

Class B 22 Medium 1,288

Class B 26 Large 1,330

Combo A 9 Medium 1,371

Combo A 12 Large 1,401

Combo B 4 Medium 1,150

Combo B 5 Large 1,210

5.3.2 Design Option Costs

Design option costs were developed independently of costs for the core cases and were 

procured through a combination of manufacturer estimates, wholesalers’ prices, list prices, and 

other sources. These data included the pricing information for components, including glass 

doors, compressors, lighting, heat exchangers, fans, and other componentry considered as design 

options. For a listing of all components considered as design options, please see section 5.6.5. 

For further details regarding the specific design options, please see section 5.6.5.

5.3.2.1 Light-Emitting Diode Price Forecasting

In the 2014 commercial refrigeration equipment final rule, DOE received comments from 

stakeholders stating that forecasts of the light-emitting diode (LED) lighting industry, including 

those performed by the Department, suggest that LED lighting is an evolving technology that 

will continue to experience significant price decreases in coming years. For this reason, in an 

effort to capture the anticipated cost reduction in LED fixtures, DOE incorporated price 

projections from its Solid State Lighting program into its MPC values for that rulemaking and 

has taken an identical approach in this BVM rulemaking due to the similar nature of the products 

and industries. The price projections for LED case lighting were developed from projections 

developed for the DOE’s Solid State Lighting program’s 2012 report, Energy Savings Potential 

of Solid-State Lighting in General Illumination Applications 2010 to 2030 (“the energy savings 

report”). In the appendix of this report, price projections from 2010 to 2030 were provided in 

$/kilolumen (klm) for LED lamps and LED luminaires. DOE analyzed the models used in the 

Solid State Lighting program work and determined that the LED luminaire projection would 

serve as an appropriate proxy for a cost projection to apply to refrigerated case LEDs.

The price projections presented in the Solid State Lighting program’s energy savings 

report are based on the DOE’s 2011 Solid State Lighting R&D Multi-Year Program Plan 

(MYPP). The MYPP is developed based on input from manufacturers, researchers, and other 

industry experts. This input is collected by the DOE at annual roundtable meetings and 
5-9

conferences. The projections are based on expectations that depend on the continued investment 

into solid-state lighting by the DOE.

DOE incorporated the price projection trends from the energy savings report into its 

engineering analysis by using the data to develop a curve of decreasing LED prices normalized 

to a base year. That base year corresponded to the year when LED price data were collected from 

catalogs, manufacturer interviews, and other sources. DOE started with this LED cost data 

specific to commercial refrigeration equipment and then applied the anticipated trend from the 

energy savings report to forecast the projected cost of LED fixtures for this equipment at the time 

of required compliance with the proposed rule (2019). These 2019 cost figures for LED fixtures,

including the emitters, drivers, wiring, and housing, were incorporated into the engineering 

analysis as comprising the LED cost portions of the MPCs for the primary equipment classes. 

DOE may continue to refine this methodology in later stages of the rulemaking analysis.

5.3.3 Representative Unit Manufacturer Production Cost Values

For each analysis point in the engineering analysis, the analytical model calculated a cost 

at the baseline, as well as a cost at each design option level above the baseline up to the max-tech 

level. This was achieved by starting with the core case cost, developed as discussed in section 

5.4.1, and adding to it the costs of the design options needed to represent all the components in a 

complete unit of the given equipment class. For example, a Class B refrigerated beverage 

vending machine of the medium representative size and using R-134a refrigerant would require 

the core case cost plus the cost of its evaporator and condenser coils and fans, compressor, and 

lighting to yield a baseline MPC. For units above the baseline, costs for improved design option 

levels were substituted by the analytical model in the order in which those design options were 

implemented.

5.4 MANUFACTURER SELLING PRICE

The MSP is the price of the equipment when it is sold by the manufacturer to the first 

party in the distribution chain. It includes all direct and indirect production costs, manufacturer 

markup, and the cost of shipping the units from the manufacturer to the first party in the 

distribution chain. 

The MSP is expressed as the product of the MPC and the manufacturer markup, added to 

the outbound shipping cost to the first destination in the distribution chain: 

MSP = MPC x markup + shipping. 

The markup and shipping costs are described in the following subsections. 

5.4.1 Manufacturer Markup

At each stage of the distribution chain, manufacturers, wholesalers, and distributors apply 

a markup to cover their operating costs and profit margins. In the engineering analysis, DOE 

determines a manufacturer markup and applies this markup to the MPC to arrive at the MSP for 
5-10

each equipment class. Wholesaler, distributor, and other markups are determined in the markups 

analysis (see chapter 6 of the TSD).

The manufacturer markup is a market-share-weighted average value for the industry. 

DOE developed this markup by examining several BVM manufacturers’ gross margin 

information from annual reports and Securities and Exchange Commission 10-K reports. The 

manufacturers analyzed by DOE account for approximately 70 percent of the BVM market, and 

each of these companies is a subsidiary of a more diversified parent company that manufactures 

equipment other than beverage vending machines. Because the 10-K reports do not provide 

gross margin information at the subsidiary level, the estimated markups represent the average 

markups that the parent company applies over its entire range of equipment offerings. 

In the absence of updated feedback from manufacturers for the current rulemaking, DOE 

is using an industry-wide manufacturer markup of 1.26, the markup calculated for the 2009 

BVM final rule. DOE evaluated markups for 2002 through 2007, calculating the manufacturer 

markup as 100 / (100 – average gross margin), where average gross margin is calculated as 

revenues minus cost of goods sold. To validate the information, DOE reviewed its assumptions 

with BVM manufacturers (during the 2009 BVM final rule). Although DOE did not interview 

any individual manufacturers for the preliminary analysis of the current rule, DOE will continue 

to seek interviews with manufacturers during the notice of proposed rulemaking (NOPR) phase 

of analysis and will adjust the manufacturer markup based on updated company financial 

information and feedback from manufacturers.

5.4.2 Shipping Costs

The third constituent component of the MSP, in addition to the MPC and the 

manufacturer markup, is the cost to ship the unit from the manufacturing facility to the first point 

on the distribution chain. The specific party (manufacturer or buyer) that incurs that cost for a 

given shipment may vary based on the terms of the sale, the type of account, the manufacturer’s 

own business practices, and other factors. However, for consistency, DOE includes shipping 

costs as a component of MSP. In calculating the shipping costs, DOE first gathered estimates of 

the costs to ship a full trailer of manufactured equipment an average distance in the United 

States. DOE then used the representative unit sizes to calculate a volume for each unit. Along 

with the dimensions of a shipping trailer and a loading factor to account for inefficiencies in 

packing, DOE used this cost and volume information to develop an average shipping cost for 

each equipment class directly analyzed. 

5.5 ENERGY CONSUMPTION MODEL

The energy consumption model is the second of two key analytical models used in 

constructing cost-efficiency curves and is implemented in the engineering analysis spreadsheet. 

This model estimates the DEC of refrigerated beverage vending machines in kWh/day at various 

performance levels using a design-options approach. DOE developed the energy consumption 

model, coupled with the system cost model, as a Microsoft Excel spreadsheet and is making the 

model available to the public on DOE’s website at 

http://www1.eere.energy.gov/buildings/appliance_standards/rulemaking.aspx/ruleid/73. For a 
5-11

given equipment class, the model estimates the DEC for the baseline and the DEC of levels of 

performance above the baseline. The model calculates energy consumption at each performance 

level separately. For Class A and Class B refrigerated beverage vending machines, DOE selected 

baseline design options that were representative of those observed in the baseline-level 

equipment selected for teardowns and that resulted in DECs at, or very close to, the standard 

level established in the 2009 BVM final rule. Because of the discretized nature of many of the 

design options, modeling the standard level exactly was not always possible. Different baseline 

design options were selected for units of the same size using carbon dioxide refrigerant rather 

than R-134a refrigerant due to the different daily energy consumptions associated with some of 

the design options for equipment using the different refrigerant. For combination vending 

machines, which currently do not have applicable standards, DOE based its modeled 

configuration of baseline equipment configurations on the designs that it had seen in other 

unregulated refrigerated beverage vending machine markets, namely the designs of Class A and 

Class B equipment prior to compliance with the 2009 BVM final rule. For each baseline level, 

DOE calculated a corresponding MPC using the cost model (described in section 5.3 ). For each 

level above the baseline, DOE used the cost increases of the various design options to recalculate 

the MPC.

5.5.1 Screened-In Technologies

In the market and technology assessment (chapter 3 of the TSD), DOE defined an initial 

list of technologies that could potentially be used to reduce the energy consumption of 

refrigerated beverage vending machines. DOE then analyzed the following technology options:

• higher efficiency lighting,

• higher efficiency evaporator fan motors,

• higher efficiency evaporator fan blades,

• improved evaporator design,

• low-pressure differential evaporators,

• improvements to anti-sweat heaters,

• improved or thicker insulation,

• higher efficiency compressors,

• variable speed compressors,

• microchannel heat exchangers,

• improved condenser design,

• higher efficiency condenser fan motors, 

• higher efficiency condenser fan blades, 

• improved glass pack design (for Class A machines),

• lighting controls, and

• low-power refrigeration controls, timers, and/or sensors. 

5.5.2 Screened-In Technologies Not Considered in the Engineering Analysis

In the screening analysis (chapter 4 of the TSD), DOE narrowed this list by eliminating 

those technologies that can reduce annual energy consumption of refrigerated beverage vending 
5-12

machines but do not reduce DEC. DOE then screened out those technologies that were not 

feasible, were not practical to manufacture, reduced equipment utility, or were considered 

unsafe.

The remaining list of screened-in technologies became an input to the engineering 

analysis. However, for reasons noted subsequently, DOE did not incorporate all of these 

technologies in the energy consumption model. These excluded technologies include higher 

efficiency evaporator and condenser fan blades, low-pressure differential evaporators, 

improvements to anti-sweat heaters, and variable speed compressors.

5.5.2.1 Higher Efficiency Evaporator and Condenser Fan Blades

Higher efficiency evaporator and condenser fan blades reduce motor shaft power 

requirements by moving air more efficiently. Current BVM designs use stamped sheet metal or 

plastic axial fan blades. These fan blades are lightweight and inexpensive. DOE was not able to 

identify any fan blade technology that is significantly more efficient than what is currently being 

used.

5.5.2.2 Low-Pressure Differential Evaporators

Low-pressure differential evaporators reduce energy consumption by reducing the power 

required by evaporator fan motors. However, in space-constrained equipment, such as 

refrigerated beverage vending machines, this reduction usually comes from a decrease in 

evaporator coil surface area, which generally requires a lower saturated evaporator temperature 

(SET) to achieve the same discharge air temperature and cooling potential, which reduces 

compressor efficiency. Because of these competing effects, DOE did not consider low-pressure 

differential evaporators as a design option.

5.5.2.3 Improvements to Anti-Sweat Heaters

Some refrigerated beverage vending machines with glass fronts are equipped with antisweat heaters whose field energy consumption can be decreased by use of technology options 

such as anti-sweat heater controls, which match the run time of anti-sweat heaters to the antisweat heating requirements imposed by the ambient humidity. However, DOE conducted an 

examination of manufacturer literature and BVM performance information and found that BVM

anti-sweat heaters are not typically designed to run at the DOE test procedure test conditions of 

75°F and 45% relative humidity. Therefore, DOE modeled all analysis points as using no antisweat heater power when tested to the DOE test procedure, and no design options for reducing 

the anti-sweat heater energy consumption were considered in the engineering analysis. 

5.5.2.4 Variable-Speed Compressors

Variable-speed compressors reduce energy consumption under field conditions by 

matching their capacity to the refrigeration load, which can change due to variations in ambient 

conditions and product loading. This technology eliminates the inefficiencies that occur due to 

mismatched capacity and load in a single-speed compressor during part-load operation. Under 
5-13

steady-state conditions such as those in the DOE test procedure, a variable-speed compressor 

running continuously eliminates the need for compressor cycling and the associated 

inefficiencies and therefore may decrease the energy consumption of the unit. DOE has seen 

some anecdotal reports that variable-speed compressors operating in temperature and capacity 

ranges appropriate for BVM applications may be available on the market. However, DOE was 

unable to procure any data on the performance of refrigeration equipment using these 

compressors and therefore did not consider variable-speed compressors in the engineering 

analysis at this time. DOE is seeking further information, including detailed performance 

specifications, which would enable accurate modeling of the performance and cost impacts of 

variable-speed compressors at later stages of this rulemaking. 

5.5.2.5 Microchannel Heat Exchangers

Microchannel heat exchangers have increased refrigerant-side heat transfer and require 

lower fan power for the same capacity as compared to tube-and-fin heat exchangers. However, 

DOE was unable to procure any data on the performance of refrigeration equipment using 

microchannel heat exchangers and therefore did not consider them in the engineering analysis at 

this time. DOE is seeking further information, including detailed performance specifications, 

which would enable accurate modeling of the performance and cost impacts of microchannel 

heat exchangers at later stages of this rulemaking.

5.5.3 Design Options

After conducting the screening analysis and removing from consideration those 

technologies described previously, the following technologies were implemented as design 

options in the energy consumption model:

• higher efficiency lighting,

• higher efficiency evaporator fan motors,

• improved evaporator design,

• improved or thicker insulation,

• higher efficiency compressors, 

• improved condenser design,

• higher efficiency condenser fan motors, 

• improved glass pack design (for Class A machines),

• lighting controls, and

• low-power refrigeration controls, timers, and/or sensors. 

Each design option has two to four technology levels, ranging from baseline performance 

to the most energy-efficient technology. The design options and the technology levels for each 

design option are described here.

5.5.3.1 Higher Efficiency Lighting

Lighting is an important characteristic of refrigerated beverage vending machines: it 

makes the product visible to the consumer in Class A machines and provides product advertising 
5-14

for Class B machines (and the analogous types of combination machines). Lighting systems 

typically operate continuously and provide an opportunity for significant energy savings. As 

lighting system efficiency increases, total energy consumption can be decreased by reducing the 

lighting system’s electricity consumption and the heat inside the refrigerated volume of Class A 

machines, which reduces the work of the compressor. For Class B machines, increasing lighting 

system efficiency only reduces direct energy consumption, because lamps and ballasts are placed 

outside the refrigerated space. 

It is important that machine (in the case of Class B machines) or vended product (in the 

case of Class A machines) illumination not degrade with higher design option levels, because 

this would decrease equipment utility. Therefore, DOE maintained constant levels of effective 

illumination across the lighting design options. This approach meant that DOE had to consider 

lighting as a system, rather than distinguishing lamps and ballasts as separate design options. 

This approach becomes more important when considering LED lighting systems, which do not 

use ballasts as fluorescent lighting systems do.

Although LED systems generally have lower efficacy than fluorescent systems, the 

fixtures used with LEDs direct light more efficiently. Although the total lumen output of LED 

systems is lower than that of comparable fluorescent systems, the amount of light incident on a 

surface (illuminance) is roughly equivalent. In the rulemaking that culminated in the 2009 BVM 

final rule, BVM manufacturers, lighting manufacturers, and other technical experts indicated that 

current LED technology provides adequate product lighting for Class A machines, and in most 

cases is comparable to fluorescent lighting. At that time, for Class B machines, BVM 

manufacturers indicated that they were still exploring LED technology, despite the lower lumen 

outputs. LED use for Class A machine lighting was found to be prevalent in teardowns 

conducted for the current rulemaking.

To account for variations in design between equipment classes, DOE used two lighting 

design options in the energy-consumption model. The first was for Class A and Combo A 

machines, and the second was for Class B and Combo B machines.

Class A and Combo A machines illuminate the beverage containers being vended. 

Lamps must be sized to fit within the refrigerated space. For fluorescent design options, DOE 

used 4-foot fluorescent lamps, based on the size of machines currently on the market. Some 

analysis points had a baseline of T8 fluorescent lamps with electronic ballasts, based on 

teardowns and market data. The remaining analysis points had a baseline lighting design option 

of LEDs, in which case no lighting improvement was considered as part of the engineering 

analysis.
5-15

Table 5.5.1 Performance Details for “Class A Lighting” Design Option

Level Description Lamp Type

Lamp 

Rated 

Power 

[watts (W)]

Lamp 

Rated Light 

Output 

[Lumens]

System 

Efficacy 

[Lumens/

W]

System 

Light 

Output 

[Lumens]

T8 4-ft T8, Electric F32T8 (2) 32.0 2,850 85.0 2,679

LED 4-ft LED 4-ft LED 11.6 625.6 53.9 625.6

Class B and Combo B machines typically use T8 fluorescent lamps to attract attention to 

the machine and to signal that the machine is functioning. As in the 2009 BVM final rule, DOE 

used a 4-foot and a 2-foot T8 lamp as the baseline lighting design option in Class B machines, 

and used the same lighting design option in Combo B analysis. LED lighting was considered as a 

design option. 

Table 5.5.2 Performance Details for “Class B Lighting” Design Option

Level Description Lamp 

Type

Lamp 

Rated 

Power 

[W]

Lamp 

Rated 

Light 

Output 

[Lumens]

System 

Efficacy 

[Lumens/W]

System 

Light 

Output 

[Lumens]

T8 2-ft. T8 & 4–ft. T8 

Electric

F17T8 & 

F32T8 49.0 4,250 90.4 3,910

LED 6-ft. LED - 34.0 2001 59.2 2001

5.5.3.2 Higher Efficiency Evaporator Fan Motors

In conjunction with fan blades, fan motors are necessary to transfer heat from the 

refrigerated space to the refrigerant. As motor efficiency increases, energy consumption 

decreases due to a direct reduction in electricity consumption and waste heat inside the 

refrigerated space.

Table 5.5.3 shows details for the evaporator fan motor design option. Currently, DOE 

considers shaded-pole motors (SPM) as the minimum technology seen in the BVM market, 

permanent split capacitor (PSC) motors as the mid-level technology, and brushless direct current 

(DC) or electronically commutated motors (ECMs) as the maximum technology. The baseline 

evaporator fan technology used by DOE varied at different analysis points based on observations 

during equipment teardowns, information in manufacturer literature, and differing standard level 

energy consumption requirements. Class A and Class B equipment was modeled as using 

evaporator fans with a rated power of 9W, while combination vending machines were modeled 

as using evaporator fans with a rated power of 6W. The motor efficiencies listed in Table 5.5.3

are the same that were used in the analysis for the rulemaking leading to the 2009 BVM final 

rule, as DOE is not aware of any significant change in the performance of these types of motors 

since that time. 
5-16

Table 5.5.3 Performance Details for “Evaporator Fan Motor” Design Option

Rated Power

[W]

Shaded-Pole Motor (SPM) Permanent Split Capacitor 

(PSC) Motor

Brushless DC Motor

(ECM)

Actual 

Power

[W]

Efficiency

Actual 

Power

[W]

Efficiency

Actual 

Power

[W]

Efficiency

9.0 53.0 17.0% 21 42.9% 12.5 72.0%

6.0 40.0 15.0% 15 40.0% 8.5 70.6%

In the energy consumption model, evaporator fans were assumed to run whenever the 

compressor is running, plus an additional 90 minutes per day in order to accomplish off-cycle 

defrost. This is based on incorporation of off-cycle evaporator fan controls in the analysis 

resulting in the 2009 final rule standard levels for Class A and Class B machines.

5.5.3.3 Improved Evaporator Design

Evaporator coils are another component necessary to transfer heat from the refrigerated 

space to the refrigerant. Table 5.5.4 and Table 5.5.5 show details for the evaporator coil design 

option. Based on available information, DOE considered a baseline and a maximum technology 

level for this design option. DOE analyzed different evaporator coils given the differences in 

design load between Class A/Combo A and Class B/Combo B machines. For each level, DOE 

specified an overall UA-valuea and a coil cost. The UA-value is normalized to the standard coil, 

and the coil cost is normalized to the heat removal capacity of the coil, with a 5% cost premium 

assumed for carbon dioxide coils over R-134a coils at the analogous analysis point, based on 

equipment teardowns and subsequent cost modeling. This allowed DOE to apply these details of 

coil design across all equipment sizes and refrigerants analyzed. DOE determined that the same 

coil improvements applied to different-sized coils would result in similar performance 

improvements.

Table 5.5.4 Performance Details for “Improved Class A Evaporator Coil” Design Option

Level Description Normalized UA [-]

Normalized Coil Cost 

[$/Btu/h]

(for R-134a coils)

AEV1 Standard Coil 1 $0.0116 

AEV2 High-Performance Coil 1.399 $0.0146 

 a The overall UA-value is the product of the overall heat transfer coefficient (British thermal units per hour (Btu/h)-

ft2

-°F) and the total surface area (ft2) of the coil. This value can be derived from the total heat transfer rate of the 

coil (Btu/h) divided by the log mean temperature difference of the air and refrigerant flows (ΔTLM).
5-17

Table 5.5.5 Performance Details for “Improved Class B Evaporator Coil” Design Option

Level Description Normalized UA [-]

Normalized Coil Cost 

[$/Btu/h]

(for R-134a coils)

BEV1 Standard Coil 1 $0.0125

BEV2 High-Performance Coil 2.43 $0.0131

The details of coil construction (shown in Table 5.5.6 and Table 5.5.7) were based on a 

baseline and prototype high-performance coil evaluated by analytical modeling performed by an 

outside subject matter expert. The baseline coil features were based on specific designs currently 

found on the market and documented through equipment teardowns. The high-performance coil 

uses a combination of enhancements to the heat transfer surfaces that increased its overall UAvalue. These enhancements include tube rifling, wavy instead of flat fins, a slightly higher fin 

pitch, and higher tube pitch in both directions. In summary, these changes result in an increased 

UA-value and increased coil cost. The increase in UA-value leads to an increase in the coil SET. 

Because compressor performance is directly related to SET, reductions in total case energy 

consumption are realized through an improved energy efficiency ratio (EER) at the condensing 

unit. DOE determined that the same coil improvements applied to differently sized coils at 

different temperatures would result in similar UA-value improvements.

Table 5.5.6 Properties of Standard and Enhanced Class A Evaporator Coil

Property Standard Coil High-Performance Coil

Overall Width (in) 9 9

Overall Height (in) 9 9

Overall Depth (in) 3.125 3.125

Coil Rows Vertical 9 12

Coil Rows Deep 5 6

Number of Parallel Circuits 1 1

Tubing Material Copper Copper

Tubing Outer Diameter (in) 0.375 0.375

Tubing Wall Thickness (in) 0.02 0.02

Tubing Inner Surface Rifled Rifled

Fin Material Aluminum Aluminum

Fin Surface Wavy Wavy

Fin thickness (in) 0.01 0.01

Fin Pitch (fins per inch) 6 8
5-18

Table 5.5.7 Properties of Standard and Enhanced Class B Evaporator Coil

Property Standard Coil High-Performance Coil

Overall Width (in) 19.5 19.5

Overall Height (in) 6 6

Overall Depth (in) 2.625 2.625

Coil Rows Vertical 6 8

Coil Rows Deep 3 3

Number of Parallel Circuits 1 1

Tubing Material Copper Copper

Tubing Outer Diameter (in) 3/8 3/8

Tubing Wall Thickness (in) 0.025 0.025

Tubing Inner Surface Smooth Rifled

Fin Material Aluminum Aluminum

Fin Surface Flat Wavy

Fin Thickness (in) 0.015 0.015

Fin Pitch (fins per inch) 6 8

5.5.3.4 Insulation Increases or Improvements

Increasing or improving insulation decreases the conduction load, which reduces 

compressor energy consumption. DOE looked at two different methods of reducing the 

conduction load. The first method was a 1/8-inch change in insulation thickness in all insulated 

panels. DOE accounted for the change in core case costs attributed to insulation thickness 

increases, as well as design time, and fixture retooling. 

The second method DOE explored was changing the insulation material. Currently, 

refrigerated beverage vending machines use foamed-in-place polyurethane as the primary 

insulation material. After discussions with industry experts and BVM manufacturers, DOE 

concluded that there are no significant variations among different polyurethane foams and 

blowing agents. Thus, DOE did not consider improvements in polyurethane foams or blowing 

agents. However, DOE did consider vacuum insulated panels (VIPs) as an option for improving 

the insulation performance of the insulated walls of beverage vending machine cases. Data 

regarding VIP performance was gathered from discussions with VIP manufacturers in 

conjunction with past rulemakings on residential refrigerators and walk-in coolers and freezers. 

These discussions yielded a representative material cost for VIPs with an R-value of 30 per inch 

of thickness. This cost was then multiplied in the engineering cost model by the insulated wall 

area and thickness to produce a differential cost of upgrading from traditional foam insulation to 

VIPs. This model simulated the entire modeled case as being insulated with VIP material, and 

assumed that the VIP material would be the dominant component of the thermal performance of

the case. Additionally, as with the increased foam thickness design option, a sunk cost per unit of 

upgrading to VIPs was calculated and applied to the unit cost. This consisted of an estimate for 

the additional costs of product engineering and redesign, new production equipment, and new 
5-19

tooling, amortized over the typical equipment production lifetime and divided by the number of 

units per year. The result was a levelized cost per unit produced. 

5.5.3.5 Improved Glass Pack

An improved glass pack design option only applies to Class A and Combo A equipment. 

Improvements to the glass pack (a prefabricated assembly of glass sheets, coatings, framing, and 

fill gas) result in less heat transfer to the refrigerated volume by radiation and conduction. This 

reduces the heat load on the refrigerant and hence the compressor load, thus reducing compressor 

energy consumption. The glass pack can be improved several ways, including adding panes of 

glass, adding low-emissivity (low-E) coating, changing from air fill to argon fill, and changing 

from an aluminum frame to a vinyl frame. Rather than examine each variation as an individual 

design option, DOE looked at two different option packages, shown in Table 5.5.8. The baseline 

design option is identical in properties and performance to the “Enhanced” glass pack design 

option modeled in the 2009 BVM final rule, while the Enhanced design option was modeled in 

WINDOW 6.31 to yield U-valuesb that account for heat transfer due to radiation and conduction 

at the test conditions of the DOE test procedure. Table 5.5.9 catalogs these resulting U-values. 

Table 5.5.8 Performance Details for “Improved Glass Pack” Design Option

Variable Baseline Enhanced

Frame Material Aluminum Vinyl

Number of Panes 2 3

Glass Type: Panel 1 Clear Clear

Glass Type: Panel 2 Low-E Low-E

Glass Type: Panel 3 - Clear

Gas Fill Argon Argon

Table 5.5.9 Performance Details for “Improved Glass Pack” Design Option

Level Description

Overall U-Factor at the 

ASHRAE 32.1 75°F Test 

Condition [Btu/h-ft-°F]

DOOR 1 Baseline 0.447

DOOR 2 Enhanced 0.259

5.5.3.6 Higher Efficiency Condenser Fan Motors

Performance details for the condenser fan motor design option are identical to those 

shown in Table 5.5.3. As with evaporator fan motors, the SPM is the minimum technology 

level, the PSC motor is the mid-level technology, and the DC motor or ECM is the maximum 

 b U-value is a measure of air-to-air heat transmission (loss or gain) due to thermal conductance and the difference in 

indoor and outdoor temperatures.
5-20

technology level in the BVM equipment space. The baseline condenser fan technology used by 

DOE varied at different analysis points based on observations during equipment teardowns, 

information in manufacturer literature, and differing standard level energy consumption 

requirements. Because condenser fan motors are outside the refrigerated space, efficiency 

improvements only impact the direct electrical consumption of the motors and not the total case 

heat load.

5.5.3.7 Improved Condenser Design

Condenser coils reject heat from the refrigerant to the ambient air. Based on available 

information, DOE considered both baseline and high-performance technology levels for this 

design option. For each level, DOE specified an overall UA-value and a coil cost, shown in 

Table 5.5.10 and Table 5.5.11. The UA-value is normalized to the standard coil, and the coil 

cost is normalized to the heat removal capacity of the coil, with a 17% cost premium assumed for 

carbon dioxide coils over R-134a coils at the analogous analysis point, based on equipment 

teardowns and subsequent cost modeling. This allowed DOE to apply these details of coil design 

across all equipment sizes and refrigerants analyzed. DOE determined that the same coil

improvements applied to differently sized coils would result in similar performance 

improvements. 

Table 5.5.10 Performance Details for “Improved Class A Condenser Coil” Design Option

Level Description Normalized 

UA [-]

Normalized Coil 

Cost [$/Btu/h]

(for R-134a coils)

ACO1 Standard Coil 1 0.009

ACO2 High-Performance Coil 1.34 0.012

Table 5.5.11 Performance Details for “Improved Class B Condenser Coil” Design Option

Level Description Normalized 

UA [-]

Normalized Coil 

Cost [$/Btu/h]

(for R-134a coils)

BCO1 Standard Coil 1 0.007

BCO2 High-Performance Coil 6.38 0.010

As previously mentioned, details of coil construction (shown in Table 5.5.12 and Table 

5.5.13) were based on a baseline and prototype high-performance coil evaluated analytically by 

an outside subject matter expert. The baseline coil features were based on specific designs 

currently found on the market and documented through equipment teardowns. The highperformance coil uses a combination of enhancements to the heat transfer surfaces that increased 

its overall UA-value. These enhancements include higher fin pitch, different fin shape, and 

increased tube passes without changing the external dimensions of the coils. In sum, these 

improvements give the prototype coil a higher UA-value, allowing the coil to run at a saturated 

condenser temperature (SCT) cooler than the baseline coil, while maintaining the same heat 
5-21

rejection rate. Because compressor performance is directly related to SCT, reductions in total 

case energy consumption are realized through an improved EER at the condensing unit. 

Table 5.5.12 Properties of Standard and Enhanced Class A Condenser Coil

Property Standard Coil High-Performance Coil

Overall Width (in) 8 8

Overall Height (in) 11 11

Overall Depth (in) 2.5 2.5

Rows Vertical 11 14

Rows Deep 4 5

Number of Parallel Circuits 1 1

Tubing Material Copper Copper

Tubing Outer Diameter (in) 0.32 0.32

Tubing Wall Thickness (in) 0.02 in 0.02 in

Tubing Inner Surface rifled rifled

Fin Material Aluminum Aluminum

Fin Surface wavy wavy

Fin Pitch (fins per inch) 6 8

Table 5.5.13 Properties of Standard and Enhanced Class B Condenser Coil

Property Standard Coil High-Performance Coil

Overall Width (in) 22 22

Overall Height (in) 12 12

Overall Depth (in) 0.75 0.75

Rows Vertical 12 15

Rows Deep 1 1

Number of Parallel Circuits 1 1

Tubing Material Copper Copper

Tubing Outer Diameter (in) 0.332 0.332

Tubing Wall Thickness (in) 0.02 in 0.02 in

Tubing Inner Surface Smooth Smooth

Fin Material Aluminum Aluminum

Fin Surface Flat Wavy

Fin Pitch (fins per inch) 8 10

5.5.3.8 Higher Efficiency Compressors

In conducting teardowns for Class A and Class B equipment, DOE found that a single 

compressor, the Embraco FFU130HAX, is widely used in those units of all sizes subject to 

standards under the 2009 BVM final rule. Accordingly, DOE incorporated the performance 
5-22

profile of this single-speed hermetic compressor into the energy consumption model as the 

baseline performance for its analyses of Class A and Class B equipment using R-134a 

refrigerant. Combination vending machines, which are not currently subject to standards and 

therefore may exhibit different levels of energy performance than that seen in regulated designs, 

were modeled as having baseline compressor performance equivalent to what was typical in the 

unregulated market at the time of the 2009 BVM final rule analysis. Data from a range of 

compressors was included in the performance model in the form of a lookup table, and 

appropriately sized compressors were referenced when developing each combination vending 

machine design-option curve (see section 5.5.7.2 for information on the calculation of 

compressor energy consumption).

Above the baseline level, reductions in total energy consumption can be realized by a 

reduction in compressor power consumption through the use of a higher efficiency single-speed 

hermetic compressor. Although several compressor manufacturers produce high-efficiency 

compressors, few data are currently available on their performance. Therefore, DOE 

approximated a set of high-efficiency compressors by adjusting the power consumption of the 

standard compressors using a constant multiplier. For combination vending machine analysis 

points, this multiplier was the equivalent of moving to the baseline compressor used in the Class 

A and Class B analysis. For Class A and Class B analyses points, these multipliers were 1.02 on 

energy consumption and 1.05 on cost, which DOE developed research and consultation with 

experts.

Because of the limited availability of compressor performance data for carbon dioxide 

refrigerant compressors, DOE applied multipliers on both the energy consumption and cost of 

the baseline and higher-efficiency compressors used for the R-134a analysis points to represent 

the performance of carbon dioxide compressors for the corresponding analysis points. The 

multipliers were 1.06 on energy consumption and 1.5 on cost. The compressor energy 

consumption multiplier was developed from rulemaking testing conducted by DOE. 

5.5.3.9 Lighting Controls

Lighting controls reduce energy consumption by dimming or turning off lighting during 

periods of low vending activity. This reduces direct component energy use as well as, in 

equipment that has lighting inside the refrigerated volume, reduces compressor energy use by

reducing the cabinet heat load. In its analyses, DOE considered lighting controls that turn off all 

signage or product lighting as a design option, and assumed that the controls would be set to 

power down the lighting for the full six hours proposed to be allowed within the DOE test 

procedure. 

5.5.3.10 Refrigeration Low Power States

The amended DOE test procedure for refrigerated beverage vending machines grants a 

3% energy consumption credit for those units that are equipped with refrigeration low power 

states. Accordingly, in its analysis, DOE included a refrigeration low power state design option 

in the form of a multiplier on the energy consumption output of the energy consumption 
5-23

spreadsheet model. For a full discussion of the methodology used to derive the multiplier, please 

see the 2014 BVM test procedure (TP) NOPR.

5.5.4 Baseline Specifications

DOE defined baseline specifications for each equipment class. These specifications 

include dimensions, numbers of components, temperatures, nominal power ratings, and other 

case features that are necessary to calculate the energy consumption of each equipment class. In 

conjunction with the lowest technological level of each design option (see section 5.5.3), the 

baseline specifications define the energy consumption and cost of the typical lowest-efficiency 

equipment on the market. Table 5.5.14 shows the specifications and units that are defined for 

each equipment class.

Table 5.5.14 Baseline Specifications

Specification Units

Refrigerated Volume ft3

Number of Lamps in Refrigerated Volume -

Number of Lamps not in Refrigerated Volume -

Number of Ballasts in Refrigerated Volume -

Number of Ballasts not in Refrigerated Volume -

Evaporator Fan Nominal Rated Wattage W (Watts)

Number of Evaporator Fans -

Condenser Fan Nominal Rated Wattage W

Number of Condenser Fans -

Average Refrigerated Volume Temperature F (Fahrenheit)

Nominal SET F

Nominal SCT F

Nominal Discharge Air Temperature (DAT) F

Nominal Compressor Sizing Btu/h

Solid Wall Area (including the door for Class B Machines) ft2

Glass Area ft2

Baseline Air Infiltration lb/hour

Load from Electronic Components (bill changers, LED displays, etc.) kWh

For Class A and Class B equipment, DOE used the same baseline specifications that were 

used in the 2009 BVM final rule, reaffirmed through stakeholder comments at the framework 

stage. Baseline specifications for combination vending machines were developed by reviewing 

available manufacturer data, selecting several representative units from available manufacturer 

data, and then aggregating the physical characteristics of the selected units. The results of this 

information were used in conjunction with information received in comments on the 2013 BVM 

framework to establish the baseline specifications for combination vending machines. 
5-24

The baseline specifications were chosen so that Class A and Class B baseline machines 

met the standard levels prescribed in the 2009 BVM final rule, and combination vending 

machines exhibited generally analogous performance to what was typical in the BVM market 

before that rulemaking. This process created a representative unit for each equipment class with 

average characteristics for physical parameters (e.g., volume, wall area), and typical performance 

for energy-consuming components (e.g., fans, lighting). Table 5.5.15 and Table 5.5.16 show the 

results for each equipment class and size. Table 5.5.15 and Table 5.5.16 also include the 12-oz. 

can capacity of each size machine, for reference. 

Table 5.5.15 Class A Equipment Class Baseline Specifications

Specification Small Medium Large

Refrigerated Volume [ft3] 17 22 34

12 oz. Can Capacity [#] 300 400 500

Number of Lamps in Refrigerated Volume [#] 2 2 2

Number of Lamps not in Refrigerated Volume [#] 0 0 0

Number of Ballasts in Refrigerated Volume [#] 0 0 0

Number of Ballasts not in Refrigerated Volume [#] 1 1 1

Evaporator Fan Nominal Rated Wattage [W] 9 9 9

Number of Evaporator Fans [#] 1 1 1

Condenser Fan Nominal Rated Wattage [W] 9 9 9

Number of Condenser Fans [#] 1 1 1

Average Refrigerated Volume Temperature [F] 36 36 36

Nominal SET [F] 8 8 8

Nominal SCT [F] 95 95 95

Nominal Discharge Air Temperature (DAT) [F] 19 19 19

Nominal Compressor Sizing [Btu/h] 1573 1722 2109

Solid Wall Area (including the door for Class B Machines) [ft2] 68 76 89

Glass Area [ft2] 11 12 16

Baseline Air Infiltration [lb/hour] 7 8 11

Load from Electronic components (bill changers, LED displays, 

etc.) [kWh] 0.45 0.45 0.45
5-25

Table 5.5.16 Class B Equipment Class Baseline Specifications

Specification Small Medium Large

Refrigerated Volume [ft3] 17 22 26

12 oz. Can Capacity [#] 450 650 800

Number of Lamps in Refrigerated Volume [#] 0 0 0

Number of Lamps not in Refrigerated Volume [#] 2 2 2

Number of Ballasts in Refrigerated Volume [#] 0 0 0

Number of Ballasts not in Refrigerated Volume [#] 1 1 1

Evaporator Fan Nominal Rated Wattage [W] 9 9 9

Number of Evaporator Fans [#] 1 1 1

Condenser Fan Nominal Rated Wattage [W] 9 9 9

Number of Condenser Fans [#] 1 1 1

Average Refrigerated Volume Temperature [F] 39 39 39

Nominal SET [F] 12 12 12

Nominal SCT [F] 98 98 98

Nominal Discharge Air Temperature (DAT) [F] 27 27 27

Nominal Compressor Sizing [Btu/h] 1287 1496 1702

Solid Wall Area (including the door for Class B Machines) [ft2] 78 90 102

Glass Area [ft2] 0 0 0

Baseline Air Infiltration [lb/hour] 9 14 17

Load from Electronic components (bill changers, LED displays, 

etc.) [kWh] 0.2 0.2 0.2

Table 5.5.17 Combination Vending Machine Equipment Class Baseline Specifications

Specification Combo A 

Medium

Combo A 

Large

Combo B 

Medium

Combo B 

Large

Refrigerated Volume [ft3] 9 12 4 5

12 oz. Can Capacity [#] 96 120 115 200

Number of Lamps in Refrigerated Volume [#] 1 1 0 0

Number of Lamps not in Refrigerated Volume [#] 1 1 2 2

Number of Ballasts in Refrigerated Volume [#] 0 0 0 0

Number of Ballasts not in Refrigerated Volume [#] 1 1 1 1

Evaporator Fan Nominal Rated Wattage [W] 6 6 6 6

Number of Evaporator Fans [#] 1 1 1 1

Condenser Fan Nominal Rated Wattage [W] 6 6 6 6

Number of Condenser Fans [#] 1 1 1 1

Average Refrigerated Volume Temperature [F] 36 36 39 39

Nominal SET [F] 8 8 12 12

Nominal SCT [F] 95 95 98 98

Nominal Discharge Air Temperature (DAT) [F] 19 19 27 27

Nominal Compressor Sizing [Btu/h] 1484 1589 1522 1656

Solid Wall Area (including the door for Class B Machines) [ft2] 75 83 51 67

Glass Area [ft2] 12 13 0 0

Baseline Air Infiltration [lb/hour] 5 6 9 10

Load from Electronic components (bill changers, LED displays, 

etc.) [kWh] 0.45 0.45 0.2 0.2
5-26

5.5.5 Non-Numerical Assumptions

In developing the energy consumption model, DOE made certain non-numerical 

assumptions concerning the analysis. These include general assumptions about the analysis as 

well as specific assumptions about load components and design options.

DOE assumed that all conditions are based on new equipment tested in a controlledenvironment chamber and subjected to the methods of testing and rating in the 2014 DOE TP 

NOPR. Manufacturers that certify their equipment to comply with Federal standards are 

required to test new units using this method, which specifies ambient temperature, humidity, 

light level, and other requirements.

5.5.6 Numerical Constants and Assumptions

In developing the energy consumption model, DOE identified constants and made 

assumptions concerning numerical values used in the analysis. These include ambient 

conditions, financial assumptions, and parameters necessary to calculate the component and nonelectric loads. Details of these assumptions are shown in Table 5.5.18 and Table 5.5.19 below.
5-27

Table 5.5.18 Energy Consumption Model Numerical Constants and Assumptions 

Numerical Constants and Assumptions Value Source

Test Chamber Temperature [°F] 75 DOE Test Procedure (10 CFR 431.294)

Test Chamber Relative Humidity [%] 45 DOE Test Procedure (10 CFR 431.294)

Test Chamber Pressure [pounds per square 

in (psi), absolute] 14.7 Assumed

Manufacturer Markup [$/$] 1.26 Publicly available corporate financial data; 

discussions with manufacturers.

List Price Markup [$/$] 2.00 Assumed

Evaporator Fan(s) Run Time Per Day [hr] 24 or less, 

Less than 24 hours if the evaporator fan motor 

control option is selected, based on discussions 

with manufacturers

Off-cycle defrost time per day if 

Evaporator Fan Control is Enabled [hr] 1.5 Assumed

R Value of Foam Insulation [ft2F·h/Btu·in] 8 Discussions with foam manufacturers; 

manufacturer data sheets

Effective R Value of Vacuum Insulated 

Panels [ft2·°F·h/Btu·in] 10 Discussions with manufacturers

Convective Film Coefficient Inside Case 

Walls With Evap Fan On [Btu/h-ft2-F] 4.00 Communication with RTTC

Convective Film Coefficient Inside Case 

Walls With Evap Fan Off[Btu/h-ft2-F] 1.00 ASHRAE Handbook–Fundamentals 2005

Convective Film Coefficient Outside Case 

Walls [Btu/h-ft2-F] 1.46 Communication with RTTC

Evaporator Coil Overall Bypass Factor 

[%] 17 DOE estimate

Density of Air @ Test Temperature [lb/ft3] 0.073 ASHRAE Handbook–Fundamentals 2005

High-Efficiency Compressor Cost 

Premium Interviews with compressor manufacturers

High-Efficiency Compressor Power 

Reduction Public comment during 2014 CRE rulemaking

Electricity Cost [$/kWh] 0.08

Commercial Building Energy Consumption 

Survey (CBECS), Energy Information 

Administration (EIA), average commercial price in 

2004

Portion of combination vending machine 

vending volume that is refrigerated 40 Manufacturer comment on 2013 BVM framework
5-28

Table 5.5.19 Engineering Constants 

Numerical Constants and Assumptions Number Source

Specific Heat of Air @ Test Conditions 

[Btu/lb-R] 0.24 Thermodynamics by Cengel and Boles, 4th edition, 2002

Latent Heat of Vaporization of Water/Water 

Vapor @ Test Temp [Btu/lb] 1050 Thermodynamics by Cengel and Boles, 4th edition, 2002

Latent Heat of Fusion of Water/Ice [Btu/lb] 143.5 ASHRAE Handbook–Fundamentals 2005

Conversion from Watts to Btu/h [Btu/h-W] 3.415179 ASHRAE Handbook–Fundamentals 2005

5.5.7 Model Components

Figure 5.5.1 shows the components of the energy consumption model. The model 

calculates DEC in two major subsections: component energy consumption and compressor 

energy consumption. Component energy consumption is the sum of electrical energy directly 

consumed by each fan motor and lamp. Compressor energy consumption is calculated from the 

total heat load (expressed as Btu/h). 

The total heat load is the sum of the component load and the non-electric load. The 

component load is a sum of the heat emitted by evaporator fan motors and lighting inside the 

refrigerated space. (Condenser fan motors are outside the refrigerated space and do not 

contribute to the component heat load.) The non-electric load is the sum of the heat contributed 

by radiation through glass (for Class A machines), heat conducted through walls and doors, and 

warm air infiltration.
5-29

Figure 5.5.1 Components of the Energy Consumption Model

5.5.7.1 Component Energy Consumption

Component energy consumption is the sum of electrical energy directly consumed by 

each fan motor and light fixture. 

Fan motor energy consumption is calculated by summing the power draw of each 

evaporator and condenser fan motor, and multiplying the total motor power by the total running 

time over 24 hours. This analysis assumed condenser fans only run when the compressor is on. 

The evaporator fan is assumed to run 24 hours a day, unless the evaporator fan motor control 

option is selected. In this case, the evaporator fan motor is off during compressor off-cycle times 

except for defrost periods. 

Lighting energy consumption is calculated by summing the power draw of each lamp and 

ballast, and multiplying the total by the total operating time of the lighting system over a 24-hour 

period. 

5.5.7.2 Compressor Energy Consumption

DOE calculated compressor energy consumption (CEC) using the compressor model 

described in section 6.4 of Air-Conditioning and Refrigeration Institute (ARI) Standard 540-

Total Heat 

Load 

[Btu/h]

Component 

Load

[Btu/h]

Non-Electric 

Load

[Btu/h]

Fan Motor 

Heat Load

[Btu/h]

Lighting Heat 

Load

[Btu/h]

Radiation 

Load

[Btu/h]

Conduction 

Load

[Btu/h]

Infiltration 

Load

[Btu/h]

Daily Energy 

Consumption [kWh/day]

Compressor 

Energy 

Consumption 

[kWh/day]

Compressor Model 

(ARI 540)

Electric Energy 

Consumption

[kWh/day]

Heat Load 

[Btu/h]

Legend:

Component 

Energy 

Consumption 

[kWh/day]

Fan Motor 

Energy

 Consumption 

[kWh/day]

Lighting 

Energy 

Consumption 

[kWh/day]
5-30

2004, Performance Rating of Positive Displacement Refrigerant Compressors and Compressor 

Units. This model is based on a 10-coefficient polynomial derived from empirical compressor 

performance data for power, mass flow, current, and efficiency. The coefficients are derived for 

each of these parameters as a function of SET and SCT. Compressor coefficients, or tabulated 

empirical data (from which coefficients can be derived), are available from compressor 

manufacturers. Similar to the method used for remote condensing equipment, the EER of any 

compressor can be determined given the SET and SCT. 

5.5.7.3 Component Load Model

The component load is the sum of the heat emitted by the evaporator fan motor and lamps 

inside the refrigerated volume. This waste heat must be removed by the compressor.

DOE assumed that all electrical energy consumed by the evaporator fan motors ends up 

as heat inside the refrigerated space. In any electric motor, irreversibilities in the motor 

windings, bearings, and other mechanical components convert much of the input electrical 

energy into heat. The rest of the energy is converted to moving air inside the case. This moving 

air is slowed by friction and eventually converted to heat as well.

DOE assumed that all electrical energy consumed by lamps and ballasts inside the 

refrigerated space ends up as heat inside that space. For lighting components outside the 

refrigerated space, DOE attributed a fraction of the electrical energy consumed to added heat 

inside that space. DOE believes that, even though the lighting components are not inside the 

refrigerated volume, they are contained within the machine envelope and contribute some heat 

through conduction to the refrigerated space. 

5.5.7.4 Radiation Load Model

The radiation heat load model accounts for the gray-body radiation between the warm 

surfaces of the surrounding environment (the test chamber) and the cold inner surfaces of the 

refrigerated space through the glass doors of Class A machines. The net radiation is incorporated 

into the overall U-value of the door calculated by WINDOW (see Table 5.5.9 for the U-values 

calculated). Within the WINDOW program, the environmental conditions in the refrigerated 

volume and the test chamber were specified to match the test conditions specified in the DOE 

test procedure. See section 5.5.7.5 for a discussion of the calculation of the combined radiation 

and conduction loads for glass doors and other glass.

5.5.7.5 Conduction Load Model

The conduction load model accounts for the heat conducted through walls and doors. For 

solid walls and doors, the conduction load is given by:
5-31

Q A

T T

h

d

k h

cond walls

room case

o

ins

ins i

= −

+ +

1 1 Eq. 5.1 

Where:

Awalls = the area of the exterior of the refrigerated volume (ft2),

ho = the convective film coefficient on the outside of refrigerated volume walls (Btu/hft2

-°F),

hi = the convective film coefficient on the inside of refrigerated walls (Btu/h-ft2-°F),

dins = the insulation thickness (in), and

kins = the insulation thermal conductivity (Btu-in/h-ft2-°F).

Because of its high thermal conductivity, the sheet metal that encloses the insulation does 

not have any significant effect on the conduction load, and therefore was not included in the 

calculation of conduction load. See Table 5.5.18 for numerical constants pertaining to the 

conduction model.

For glass doors, the conduction load is incorporated into the overall U-factor of the door 

assembly or glass calculated by WINDOW. (See Table 5.5.9 for the U-values calculated.) The 

combined radiation and conduction load for glass doors and other glass is calculated as:

Qglass = Uoverall Aglass (Troom − Tcase ) Eq. 5.2

Where:

Uoverall = the overall U-factor, including convection and radiation (Btu/h-ft2-°F), and

Aglass = the area of the glass (ft2

).

5.5.7.6 Infiltration Load Model

The infiltration load model accounts for the heat that is added to a refrigerated beverage 

vending machine when warm, moist air enters the case (primarily through leaks and vending 

doors). The infiltration load is difficult to simulate analytically because of the inherent 

complexity of the fluid phenomena of infiltration. Therefore, DOE used empirical data on 

defrost melt water generation to back-calculate the infiltration loads. This approach was 

developed during the 2009 BVM rulemaking proceeding using empirical data for infiltration 

loads provided by Southern California Edison’s Refrigeration and Thermal Test Center (RTTC) 

from beverage vending machine testing. The values developed at that time were retained in the 

current analysis due to the absence of data or comments to the contrary. 

Ambient room air infiltrated into the refrigerated space contributes to the load in two 

ways: a sensible load in the form of the heat contained in the dry air, and a latent load in the 

form of water vapor in the air that condenses on cold surfaces. Assuming the amount of 

condensation on the coil—and thus the amount of defrost melt water—is correlated to the 

amount of water that enters the case through infiltration, the defrost melt water mass flow can be 
5-32

used to estimate the mass flow of water that enters the case as water vapor in the air. Given the 

values both for the humidity level in the case and the ambient room air (known due to the fixed 

conditions of the DOE test procedure), the mass flow of air that enters the refrigerated case can 

be calculated as:

( )( ) m

m

HR HR CBF air

defrostmelt

room case

= − 1− Eq. 5.3

Where:

mair = the mass flow of dry air into the case (lbs/hr),

mdefrostmelt = the mass flow of defrost melt water (lbs/hr), 

HRroom = the humidity ratio of the ambient air in the room (dimensionless), 

HRcase = the humidity ratio of the air inside the case (dimensionless), and 

CBF = the coil bypass factor (dimensionless).

The coil bypass factor is a measure of the fraction of air in the case that is never 

influenced by the evaporator coil (or a measure of the fraction of air that does not deposit its 

moisture onto the evaporator coil). This factor allows the infiltration calculation to be correlated 

to empirical data. Communication with Southern California Edison’s RTTC during the 2009 

BVM rulemaking was used to estimate the evaporator coil bypass factor, and this figure was 

retained in the current analysis. As shown in Table 5.5.18, the coil bypass factor was estimated 

to be 17 percent.

Once the air flow rates were calculated, they were entered into DOE’s model. The mass 

flow of water vapor into the case is the mass flow of air multiplied by the difference of humidity 

ratios inside and outside the case. Using the mass flows of air and water vapor, the infiltration 

load can be approximated using:

Qinf mairCdryair (Troom Tcase ) mvapor Hv,H O = − + 2 Eq. 5.4

Where:

Qinf = the infiltration load (Btu/h),

Cair = the specific heat of dry air (Btu/lb-°F), 

mvapor = the mass flow of water vapor into the case (lbs/hr), and

Hv,H2O = the heat of vaporization of water.

5.6 COST-EFFICIENCY CURVES

The result of the engineering analysis is a set of cost-efficiency curves. DOE developed a 

total of 20 curves representing the three equipment classes, including the different refrigerants 

and machines sizes in each equipment class using the baseline specifications and design options 

described previously. The method for developing curves started with determining the baseline 

energy consumption and manufacturer production cost. Above the baseline, design options were 
5-33

implemented in order of lowest to highest payback, and only one design option was implemented 

at each design option level. Design options were implemented until all technologies were at a 

maximum level. 

The 20 cost-efficiency curves are shown in Figure 5.6.1 through Figure 5.6.20 and in 

tabular form in Table 5.6.1 through Table 5.6.20 in the form of DEC versus MSP. More detailed 

results, including the design options used at each design option level, are provided in appendix 

B. 

As stated previously, DOE used the cost-efficiency curves from the engineering analysis 

as an input to the life-cycle cost (LCC) analysis to determine the price of beverage vending 

machines to the customer (see chapter 8 of the TSD). 
5-34

Figure 5.6.1 Cost-Efficiency Curve for the R-134a Class A – Small Analysis Point

Table 5.6.1 Cost Efficiency Data for the R-134a Class A – Small Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 3.53 $2,090.03 -

1 3.32 $2,095.04 0 + Automatic Lighting Controls

2 3.12 $2,100.82 1 + Enhanced Evaporator Coil

3 3.026 $2,105.84 2 + Refrigeration Low Power State

4 2.988 $2,111.62 3 + Higher Efficiency Compressor

5 2.9 $2,126.49 4 + 1.125" Thick Insulation

6 2.871 $2,132.06 5 + Enhanced Condenser Coil

7 2.629 $2,194.40 6 + Enhanced Glass Pack

8 2.58 $2,210.84 7 + Electronically-Commutated Condenser 

Fan Motor

9 2.076 $2,830.28 8 + Vacuum Insulated Panels
5-35

Figure 5.6.2 Cost-Efficiency Curve for the R-134a Class A – Medium Analysis Point

Table 5.6.2 Cost Efficiency Data for the R-134a Class A – Medium Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 3.77 $2,138.75 -

1 3.56 $2,143.76 0 + Automatic Lighting Controls

2 3.34 $2,150.09 1 + Enhanced Evaporator Coil

3 3.24 $2,155.11 2 + Refrigeration Low Power State

4 3.191 $2,160.89 3 + Higher Efficiency Compressor

5 3.153 $2,166.98 4 + Enhanced Condenser Coil

6 3.065 $2,182.16 5 + 1.125" Thick Insulation

7 2.794 $2,250.26 6 + Enhanced Glass Pack

8 2.745 $2,266.70 7 + Electronically-Commutated Condenser 

Fan Motor

9 2.183 $2,955.05 8 + Vacuum Insulated Panels
5-36

Figure 5.6.3 Cost-Efficiency Curve for the R-134a Class A – Large Analysis Point

Table 5.6.3 Cost Efficiency Data for the R-134a Class A – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.38 $2,257.10 -

1 4.17 $2,262.11 0 + Automatic Lighting Controls

2 3.9 $2,269.86 1 + Enhanced Evaporator Coil

3 3.783 $2,274.88 2 + Refrigeration Low Power State

4 3.725 $2,280.66 3 + Higher Efficiency Compressor

5 3.618 $2,296.36 4 + 1.125" Thick Insulation

6 3.57 $2,303.83 5 + Enhanced Condenser Coil

7 3.22 $2,393.98 6 + Enhanced Glass Pack

8 3.162 $2,410.42 7 + Electronically-Commutated Condenser 

Fan Motor

9 2.493 $3,215.70 8 + Vacuum Insulated Panels
5-37

Figure 5.6.4 Cost-Efficiency Curve for the R-134a Class B – Small Analysis Point
5-38

Table 5.6.4 Cost Efficiency Data for the R-134a Class B – Small Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.45 $1,767.13 -

1 4.06 $1,768.07 0 + Enhanced Evaporator Coil

2 3.48 $1,773.09 1 + Automatic Lighting Controls

3 3.376 $1,778.10 2 + Refrigeration Low Power State

4 3.269 $1,783.65 3 + Enhanced Condenser Coil

5 3.143 $1,800.09 4 + Electronically-Commutated Evaporator 

Fan Motor

6 3.026 $1,821.76 5 + Permanent Split Capacitor Condenser Fan 

Motor

7 2.959 $1,837.03 6 + 1.125" Thick Insulation

8 2.6 $1,949.89 7 + 4 foot, LED, 3500 K

9 2.58 $1,955.67 8 + Higher Efficiency Compressor

10 2.55 $1,972.11 9 + Electronically-Commutated Condenser 

Fan Motor

11 2.13 $2,680.62 10 + Vacuum Insulated Panels
5-39

Figure 5.6.5 Cost-Efficiency Curve for the R-134a Class B – Medium Analysis Point

Table 5.6.5 Cost Efficiency Data for the R-134a Class B – Medium Analysis Point

Design 

Option 

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.73 $1,844.17 -

1 4.29 $1,845.26 0 + Enhanced Evaporator Coil

2 3.72 $1,850.28 1 + Automatic Lighting Controls

3 3.608 $1,855.29 2 + Refrigeration Low Power State

4 3.473 $1,861.74 3 + Enhanced Condenser Coil

5 3.327 $1,883.41 4 + Permanent Split Capacitor Condenser Fan 

Motor

6 3.298 $1,889.19 5 + Higher Efficiency Compressor

7 3.22 $1,904.92 6 + 1.125" Thick Insulation

8 2.862 $2,017.78 7 + 4 foot, LED, 3500 K

9 2.823 $2,034.22 8 + Electronically-Commutated Condenser 

Fan Motor

10 2.35 $2,846.61 9 + Vacuum Insulated Panels
5-40

Figure 5.6.6 Cost-Efficiency Curve for the R-134a Class B – Large Analysis Point

Table 5.6.6 Cost Efficiency Data for the R-134a Class B – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 5.07 $1,902.53 -

1 4.56 $1,903.78 0 + Enhanced Evaporator Coil

2 3.99 $1,908.79 1 + Automatic Lighting Controls

3 3.87 $1,913.81 2 + Refrigeration Low Power State

4 3.715 $1,921.14 3 + Enhanced Condenser Coil

5 3.55 $1,942.82 4 + Permanent Split Capacitor Condenser Fan 

Motor

6 3.463 $1,959.01 5 + 1.125" Thick Insulation

7 3.434 $1,964.79 6 + Higher Efficiency Compressor

8 3.075 $2,077.65 7 + 4 foot, LED, 3500 K

9 3.036 $2,094.09 8 + Electronically-Commutated Condenser 

Fan Motor

10 2.48 $3,010.11 9 + Vacuum Insulated Panels
5-41

Figure 5.6.7 Cost-Efficiency Curve for the R-134a Combo A – Medium Analysis Point
5-42

Table 5.6.7 Cost Efficiency Data for the R-134a Combo A - Medium Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 5.9 $2,026.71 -

1 5.29 $2,031.72 0 + Automatic Lighting Controls

2 4.8 $2,037.18 1 + Enhanced Evaporator Coil

3 4.31 $2,049.34 2 + Higher Efficiency Compressor

4 3.7 $2,071.01 3 + Permanent Split Capacitor Evaporator Fan 

Motor

5 2.69 $2,107.78 4 + 4 foot, LED, 3500 K

6 2.58 $2,113.04 5 + Enhanced Condenser Coil

7 2.503 $2,118.05 6 + Refrigeration Low Power State

8 2.367 $2,134.49 7 + Electronically-Commutated Evaporator 

Fan Motor

9 2.231 $2,156.17 8 + Permanent Split Capacitor Condenser Fan 

Motor

10 2.17 $2,171.32 9 + 1.125" Thick Insulation

11 2.13 $2,187.76 10 + Electronically-Commutated Condenser 

Fan Motor

12 2.03 $2,254.87 11 + Enhanced Glass Pack

13 1.67 $2,938.14 12 + Vacuum Insulated Panels
5-43

Figure 5.6.8 Cost-Efficiency Curve for the R-134a Combo A – Large Analysis Point
5-44

Table 5.6.8 Cost Efficiency Data for the R-134a Combo A – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 6.27 $2,081.77 -

1 5.65 $2,086.79 0 + Automatic Lighting Controls

2 5.11 $2,092.63 1 + Enhanced Evaporator Coil

3 4.58 $2,104.79 2 + Permanent Split Capacitor Evaporator Fan 

Motor

4 3.94 $2,126.46 3 + 4 foot, LED, 3500 K

5 2.93 $2,163.23 4 + Enhanced Condenser Coil

6 2.81 $2,168.86 5 + Refrigeration Low Power State

7 2.726 $2,173.87 6 + Electronically-Commutated Evaporator 

Fan Motor

8 2.59 $2,190.32 7 + Permanent Split Capacitor Condenser Fan 

Motor

9 2.425 $2,211.99 8 + Higher Efficiency Compressor

10 2.36 $2,227.45 9 + 1.125" Thick Insulation

11 2.32 $2,243.89 10 + Electronically-Commutated Condenser 

Fan Motor

12 2.19 $2,318.67 11 + Enhanced Glass Pack

13 1.79 $3,069.80 12 + Vacuum Insulated Panels
5-45

Figure 5.6.9 Cost-Efficiency Curve for the R-134a Combo B - Medium Analysis Point
5-46

Table 5.6.9 Cost Efficiency Data for the R-134a Combo B - Medium Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.8 $1,629.75 -

1 4.24 $1,630.86 0 + Enhanced Evaporator Coil

2 3.64 $1,635.87 1 + Automatic Lighting Controls

3 3.25 $1,642.43 2 + Enhanced Condenser Coil

4 2.84 $1,664.10 3 + Permanent Split Capacitor Evaporator Fan 

Motor

5 2.755 $1,669.12 4 + Refrigeration Low Power State

6 2.59 $1,681.27 5 + Higher Efficiency Compressor

7 2.503 $1,697.72 6 + Electronically-Commutated Evaporator 

Fan Motor

8 2.425 $1,719.39 7 + Permanent Split Capacitor Condenser Fan 

Motor

9 2.076 $1,832.25 8 + 4 foot, LED, 3500 K

10 2.05 $1,846.45 9 + 1.125" Thick Insulation

11 2.04 $1,862.89 10 + Electronically-Commutated Condenser 

Fan Motor

12 1.9 $2,332.76 11 + Vacuum Insulated Panels
5-47

Figure 5.6.10 Cost-Efficiency Curve for the R-134a Combo B – Large Analysis Point
5-48

Table 5.6.10 Cost Efficiency Data for the R-134a Combo B – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.93 $1,710.60 -

1 4.36 $1,711.81 0 + Enhanced Evaporator Coil

2 3.77 $1,716.82 1 + Automatic Lighting Controls

3 3.54 $1,723.96 2 + Enhanced Condenser Coil

4 3.434 $1,728.97 3 + Refrigeration Low Power State

5 3.026 $1,750.64 4 + Permanent Split Capacitor Evaporator Fan 

Motor

6 2.794 $1,763.09 5 + Higher Efficiency Compressor

7 2.706 $1,779.53 6 + Electronically-Commutated Evaporator Fan 

Motor

8 2.347 $1,892.39 7 + 4 foot, LED, 3500 K

9 2.289 $1,914.06 8 + Permanent Split Capacitor Condenser Fan 

Motor

10 2.25 $1,928.87 9 + 1.125" Thick Insulation

11 2.24 $1,945.31 10 + Electronically-Commutated Condenser Fan 

Motor

12 2.05 $2,551.53 11 + Vacuum Insulated Panels
5-49

Figure 5.6.11 Cost-Efficiency Curve for the R-744 Class A – Small Analysis Point

Table 5.6.11 Cost Efficiency Data for the R-744 Class A – Small Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the 

Baseline

0 3.51 $2,183.22 -

1 3.29 $2,188.24 0 + Automatic Lighting Controls

2 3.1 $2,194.31 1 + Enhanced Evaporator Coil

3 3.007 $2,199.32 2 + Refrigeration Low Power State

4 2.968 $2,205.85 3 + Enhanced Condenser Coil

5 2.929 $2,214.52 4 + Higher Efficiency Compressor

6 2.677 $2,276.86 5 + Enhanced Glass Pack

7 2.144 $2,896.31 6 + Vacuum Insulated Panels
5-50

Figure 5.6.12 Cost-Efficiency Curve for the R-744 Class A – Medium Analysis Point

Table 5.6.12 Cost Efficiency Data for the R-744 Class A – Medium Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 3.8 $2,216.20 -

1 3.59 $2,221.22 0 + Automatic Lighting Controls

2 3.37 $2,227.88 1 + Enhanced Evaporator Coil

3 3.269 $2,232.90 2 + Refrigeration Low Power State

4 3.22 $2,241.57 3 + Higher Efficiency Compressor

5 3.182 $2,248.71 4 + Enhanced Condenser Coil

6 2.9 $2,316.80 5 + Enhanced Glass Pack

7 2.852 $2,333.25 6 + Electronically-Commutated Condenser 

Fan Motor

8 2.26 $3,021.60 7 + Vacuum Insulated Panels
5-51

Figure 5.6.13 Cost-Efficiency Curve for the R-744 Class A – Large Analysis Point

Table 5.6.13 Cost Efficiency Data for the R-744 Class A – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the 

Baseline

0 4.43 $2,336.09 -

1 4.21 $2,341.11 0 + Automatic Lighting Controls

2 3.94 $2,349.25 1 + Enhanced Evaporator Coil

3 3.822 $2,354.26 2 + Refrigeration Low Power State

4 3.764 $2,362.93 3 + Higher Efficiency Compressor

5 3.715 $2,371.68 4 + Enhanced Condenser Coil

6 3.347 $2,461.83 5 + Enhanced Glass Pack

7 3.288 $2,478.27 6 + Electronically-Commutated Condenser 

Fan Motor

8 2.59 $3,283.55 7 + Vacuum Insulated Panels
5-52

Figure 5.6.14 Cost-Efficiency Curve for the R-744 Class B – Small Analysis Point
5-53

Table 5.6.14 Cost Efficiency Data for the R-744 Class B – Small Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.44 $1,843.22 -

1 4.05 $1,844.19 0 + Enhanced Evaporator Coil

2 3.48 $1,849.20 1 + Automatic Lighting Controls

3 3.376 $1,854.22 2 + Refrigeration Low Power State

4 3.259 $1,860.72 3 + Enhanced Condenser Coil

5 3.133 $1,877.16 4 + Electronically-Commutated Evaporator 

Fan Motor

6 3.026 $1,898.83 5 + Permanent Split Capacitor Condenser Fan 

Motor

7 2.997 $1,907.50 6 + Higher Efficiency Compressor

8 2.638 $2,020.36 7 + 4 foot, LED, 3500 K

9 2.609 $2,036.80 8 + Electronically-Commutated Condenser 

Fan Motor

10 2.17 $2,745.31 9 + Vacuum Insulated Panels
5-54

Figure 5.6.15 Cost-Efficiency Curve for the R-744 Class B – Medium Analysis Point

Table 5.6.15 Cost Efficiency Data for the R-744 Class B – Medium Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.73 $1,921.20 -

1 4.29 $1,922.33 0 + Enhanced Evaporator Coil

2 3.71 $1,927.35 1 + Automatic Lighting Controls

3 3.599 $1,932.36 2 + Refrigeration Low Power State

4 3.463 $1,939.91 3 + Enhanced Condenser Coil

5 3.327 $1,961.58 4 + Permanent Split Capacitor Condenser Fan 

Motor

6 3.298 $1,970.25 5 + Higher Efficiency Compressor

7 2.939 $2,083.11 6 + 4 foot, LED, 3500 K

8 2.91 $2,099.55 7 + Electronically-Commutated Condenser 

Fan Motor

9 2.396 $2,911.93 8 + Vacuum Insulated Panels
5-55

Figure 5.6.16 Cost-Efficiency Curve for the R-744 Class B – Large Analysis Point

Table 5.6.16 Cost Efficiency Data for the R-744 Class B – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 5.06 $1,980.49 -

1 4.56 $1,981.80 0 + Enhanced Evaporator Coil

2 3.99 $1,986.82 1 + Automatic Lighting Controls

3 3.87 $1,991.83 2 + Refrigeration Low Power State

4 3.715 $2,000.43 3 + Enhanced Condenser Coil

5 3.55 $2,022.10 4 + Permanent Split Capacitor Condenser Fan 

Motor

6 3.521 $2,030.77 5 + Higher Efficiency Compressor

7 3.162 $2,143.63 6 + 4 foot, LED, 3500 K

8 3.123 $2,160.07 7 + Electronically-Commutated Condenser 

Fan Motor

9 2.541 $3,076.09 8 + Vacuum Insulated Panels
5-56

Figure 5.6.17 Cost-Efficiency Curve for the R-744 Combo A – Medium Analysis Point
5-57

Table 5.6.17 Cost Efficiency Data for the R-744 Combo A – Medium Analysis Point

Design 

Option 

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 6.08 $2,085.82 -

1 5.46 $2,090.83 0 + Automatic Lighting Controls

2 4.95 $2,096.57 1 + Enhanced Evaporator Coil

3 4.24 $2,118.24 2 + Permanent Split Capacitor Evaporator Fan 

Motor

4 3.16 $2,155.02 3 + 4 foot, LED, 3500 K

5 2.78 $2,173.25 4 + Higher Efficiency Compressor

6 2.66 $2,179.41 5 + Enhanced Condenser Coil

7 2.58 $2,184.42 6 + Refrigeration Low Power State

8 2.444 $2,200.87 7 + Electronically-Commutated Evaporator Fan 

Motor

9 2.299 $2,222.54 8 + Permanent Split Capacitor Condenser Fan 

Motor

10 2.24 $2,237.69 9 + 1.125" Thick Insulation

11 2.2 $2,254.14 10 + Electronically-Commutated Condenser Fan 

Motor

12 2.09 $2,321.24 11 + Enhanced Glass Pack

13 1.71 $3,004.51 12 + Vacuum Insulated Panels
5-58

Figure 5.6.18 Cost-Efficiency Curve for the R-744 Combo A – Large Analysis Point
5-59

Table 5.6.18 Cost Efficiency Data for the R-744 Combo A – Large Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 6.46 $2,141.16 -

1 5.84 $2,146.17 0 + Automatic Lighting Controls

2 5.27 $2,152.32 1 + Enhanced Evaporator Coil

3 4.7 $2,170.55 2 + Higher Efficiency Compressor

4 4.05 $2,192.22 3 + Permanent Split Capacitor Evaporator Fan 

Motor

5 3.03 $2,228.99 4 + 4 foot, LED, 3500 K

6 2.9 $2,235.59 5 + Enhanced Condenser Coil

7 2.813 $2,240.60 6 + Refrigeration Low Power State

8 2.668 $2,257.04 7 + Electronically-Commutated Evaporator Fan 

Motor

9 2.503 $2,278.72 8 + Permanent Split Capacitor Condenser Fan 

Motor

10 2.43 $2,294.17 9 + 1.125" Thick Insulation

11 2.4 $2,310.62 10 + Electronically-Commutated Condenser Fan 

Motor

12 2.27 $2,385.39 11 + Enhanced Glass Pack

13 1.84 $3,136.52 12 + Vacuum Insulated Panels
5-60

Figure 5.6.19 Cost-Efficiency Curve for the R-744 Combo B - Medium Analysis Point
5-61

Table 5.6.19 Cost Efficiency Data for the R-744 Combo B - Medium Analysis Point

Design 

Option 

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 4.91 $1,687.32 -

1 4.33 $1,688.43 0 + Enhanced Evaporator Coil

2 3.73 $1,693.45 1 + Automatic Lighting Controls

3 3.32 $1,701.13 2 + Enhanced Condenser Coil

4 2.89 $1,722.80 3 + Permanent Split Capacitor Evaporator Fan 

Motor

5 2.803 $1,727.82 4 + Refrigeration Low Power State

6 2.629 $1,746.05 5 + Higher Efficiency Compressor

7 2.541 $1,762.50 6 + Electronically-Commutated Evaporator Fan 

Motor

8 2.464 $1,784.17 7 + Permanent Split Capacitor Condenser Fan 

Motor

9 2.105 $1,897.03 8 + 4 foot, LED, 3500 K

10 2.09 $1,911.23 9 + 1.125" Thick Insulation

11 2.07 $1,927.67 10 + Electronically-Commutated Condenser Fan 

Motor

12 1.93 $2,397.54 11 + Vacuum Insulated Panels
5-62

Figure 5.6.20 Cost-Efficiency Curve for the R-744 Class A – Small Analysis Point
5-63

Table 5.6.20 Cost Efficiency Data for the R-744 Class A – Small Analysis Point

Design 

Option

Level

Daily Energy 

Consumption 

[kWh/day]

Manufacturer 

Selling Price 

[$]

Design Option Change Above the Baseline

0 5.06 $1,769.67 -

1 4.47 $1,770.88 0 + Enhanced Evaporator Coil

2 3.87 $1,775.90 1 + Automatic Lighting Controls

3 3.63 $1,784.26 2 + Enhanced Condenser Coil

4 3.521 $1,789.27 3 + Refrigeration Low Power State

5 3.094 $1,810.95 4 + Permanent Split Capacitor Evaporator Fan 

Motor

6 2.852 $1,829.61 5 + Higher Efficiency Compressor

7 2.755 $1,846.05 6 + Electronically-Commutated Evaporator Fan 

Motor

8 2.396 $1,958.91 7 + 4 foot, LED, 3500 K

9 2.338 $1,980.58 8 + Permanent Split Capacitor Condenser Fan 

Motor

10 2.3 $1,995.39 9 + 1.125" Thick Insulation

11 2.29 $2,011.84 10 + Electronically-Commutated Condenser 

Fan Motor

12 2.09 $2,618.05 11 + Vacuum Insulated Panels
5-64

REFERENCES

1 Lawrence Berkley National Laboratory. Window. 2013. 

<http://windows.lbl.gov/software/window/6/>